Redhead

Aythya americana

Ducks in general often lay eggs in the nests of others, but the Redhead carries this to extremes. Female Redheads regularly parasitize each others' nests, as well as the nests of at least 10 other duck species. They also have been known to lay eggs in the nests of American Bittern, and even of the predatory Northern Harrier! Some females may be entirely parasitic, never incubating their own eggs. Such behavior is abetted by the social tendencies of the species, with many often nesting in close proximity. In winter, impressive flocks of Redheads concentrate on coastal lagoons; such gatherings may run to tens of thousands of individuals in the Laguna Madre of southern Texas and northeastern Mexico.

Conservation status

Total population is evidently far below original levels, a sharper decline than for most ducks. Loss of nesting habitat is probably the main cause.

Lakes, saltwater bays, estuaries; in summer, fresh marshes. For nesting season favors large marshes in prairies or intermountain valleys. Migrants gather on large lakes. In winter, mainly on coastal bays and lagoons, also on freshwater lakes inland.

Ducks in general often lay eggs in the nests of others, but the Redhead carries this to extremes. Female Redheads regularly parasitize each others' nests, as well as the nests of at least 10 other duck species. They also have been known to lay eggs in the nests of American Bittern, and even of the predatory Northern Harrier! Some females may be entirely parasitic, never incubating their own eggs. Such behavior is abetted by the social tendencies of the species, with many often nesting in close proximity. In winter, impressive flocks of Redheads concentrate on coastal lagoons; such gatherings may run to tens of thousands of individuals in the Laguna Madre of southern Texas and northeastern Mexico.

Photo Gallery

Feeding Behavior

forages by diving, usually in water a few feet deep, or by dabbling and up-ending in very shallow water. In winter on shallow coastal lagoons may do most feeding by simply dipping head underwater.

Eggs

usually 9-14, although true "normal" clutch size difficult to determine. Dull white to pale olive buff. Incubation is by female only, 23-29 days. Young: female leads young away from nest about a day they hatch. Young feed themselves; capable of flight at about 60-65 days.

Young

female leads young away from nest about a day they hatch. Young feed themselves; capable of flight at about 60-65 days.

Nesting

Nest site is in dense marsh (especially bulrushes) above shallow water, occasionally on dry ground. Bulky nest is built up of dead vegetation and anchored to standing growth, lined with down. Nesting is complicated by parasitic tendencies, typically laying eggs in nests of other Redheads and other waterbirds. Most females apparently are semi-parasites, laying several eggs in nests of other birds, then raising a clutch of their own. Several may lay eggs in a nest that is never incubated; such "dump nests" have been reported with up to 87 eggs.

Migration

Migrates in flocks. In summer, when males abandon their mates, they may fly hundreds of miles to the north to lakes where they go through the flightless stage of molt. Main migration is fairly late in fall and early in spring.

Migration

Migrates in flocks. In summer, when males abandon their mates, they may fly hundreds of miles to the north to lakes where they go through the flightless stage of molt. Main migration is fairly late in fall and early in spring.